Radio cable



Dec. 15,v 1936. E. F. ANDREWS l 2,064,513 y RADIO CABLE Filed March 9, 1931 2 Sheets-Sheet 1 Dec. 15, 1936.

E. F, ANDREWS v RADIO CABLE Filed March 9, 1951 2 Sheets-Sheet 2.

Patented Dec. 15, 1936 UNITED STATES PATENT OFFICE 16 Claims.

This invention relates to multiple cables comprising a plurality of electric conductors insulated from each other, and particularly to such cables which are suitable for use with radio receiving sets.

One of the objects of the invention is to provide an improved multiple cable.

A further object of the invention is to provide an improved multiple cable of generally flat form which may readily be concealed by iioor coverings and the like.

A further object of the invention is to provide an improved multiple cable which is of generally iiat form and which can be readily secured in desired position without endangering the conductors or the insulation thereof.

A further object of the invention is to provide a cable having an outer envelope and means associated therewith for maintaining the conductors and the like in desired position.

A further object of the invention is to provide a cable in which one or more conductors are located with respect to the others to minimize objectionable capacity effects therebetween.

A further object of the invention is to provide a multiple cable in which a certain conductor is effectively shielded from another conductor.

A further object of the invention is to provide an improved radio receiving set cable having detachable means at one end for connection to a source of power, antenna and ground, and at the other end detachable means for connection to the radio set.

A further object of the invention is to provide a portable radio receiving set and a plurality of radio cables whereby the set may be readily connected to and disconnected from a source of power, antenna and ground in a plurality of locations.

A further object of the invention is to provide a cable and radio receiving set cabinet provided with means for stowing an excess length of cable therein.

A further object of the invention is to provide a radio receiving set cable having an improved connecting means.

A further object of the invention is to provide an improved connecting plug for a radio receiv- 50 ing set cable.

Other objects, advantages and capabilities of the invention will appear from the following description of preferred embodiments of the invention, taken in conjunction with the accom- 5 panying drawings, in which (Cl. Z-16) Figure l is an elevational view, partly in section, showing a radio receiving set and cable embodying the invention:

Fig. 2 is a sectional plan view taken on the line 2-2 of Fig. 1; 5

Fig. 3 is a plan detail view of a fragment of the cable, the outer envelope being partly broken away to disclose the insulated conductors and other elements;

Fig. 4 is a sectional detail view taken on the line 4-4 of Fig. 3;

Fig. 5 is a similar View of a modified form of cable;

Fig. 6 is an enlarged sectional view of the irnproved cable plug;

Fig. 7 is a perspective view showing a modified form of cable which is readily detachable from the radio set;

Fig. 8 is a perspective detail showing the male plug element mounted on the set; and 0 Fig. 9 is a perspective view showing the modied form of cable connected to the set.

Referring to the drawings, the cable I0 cornprises an outer envelope I I which encloses a plurality of insulated conductors I2, I3, I4, and I5 and a suitable number of spacers or fillers I6.

The conductors I2, I3, I4 and I5 may suitably be rubber coated stranded copper Wires and the spacers or llers I6 may suitably be cotton cords of approximately the same size as the insulated conductors so that said conductors and spacers may be laid in a row as shown in Fig. 4 to provide a cable of generally iiat or tape-like form. The envelope II may suitably be woven around the conductors and iillers and its opposite faces may be connected by threads II which pass between adjacent conductors and llers, preserving the desired arrangement of the enclosed elements and the general fiat form of the cable. The threads I'I may be positioned during the weaving operation or during a subsequent independent operation. The weaving operation may be conducted in any suitable manner so as to produce an envelope II having a desired elongative design Woven into it.

Instead of the plurality of llers I6 I may provide a single filler of suitable width so as to provide effective spacing between the conductor I5 and the other conductors I2, I3 and I4. The conductor I5 is normally the antenna conductor, the conductor I4 may, for example, be the ground conductor, While the conductors I2 and I3 may be the alternating current conductors which are supplied with energy from the power lines.

It will readily be seen from the drawings that it is preferred to space the antenna conductor I5 as far as possible from the other conductors. This is done to reduce as far as possible the capacity between the antenna and the other conductors and to reduce the signal power loss resulting therefrom. Another advantage of this spacing is the reduction of the possibility of the antenna picking up a hum or other electrical disturbances from the power lines. The energy loss is a function of the frequency and owing to the high frequency of the radio oscillations in the antenna the signal strength loss is frequently considerable. Another objectionable effect of the capacity between the antenna and the other conductors is that it tends to put the rst tuned circuit out of step with the other circuits, which impairs the efiiciency of the operation of set.

In order to obtain the full benefit of the invention, the material of which the llers I6 are made should be of low specic inductive capacity. I have found cotton string to be suitable since it introduces a relatively small amount of solid matter between the antenna and the other conductors, 'the main dielectric being air.

n the modication shown in Fig. 5 the ground conductor it is omitted, or is replaced by a ller i@ and ground connection is made by means of a shield ES of conductive material formed on the exterior of the insulated conductors I2 and i3. The shield i2 may suitably be constituted of woven metal, although any other form of conducting coatine may be employed.

The free end of the cable i is connected to a plug i9, which may suitably comprise the prongs 29 adapted to cooperate with a conventional power outlet iii. The conductors I2 and I3 are connected to the prongs 2D in the usual manner. The plug Sti comprises a socket 22 which is connected to the antenna conductor I5, the socket 22 being adapted to receive a plug 23 of midget type, whereby the antenna lead 24 may suitably be connected to the receiving set.

The plug i!! also comprises a socket 25 to which the ground conductor i4 of the cable is connected. The socket 25 is adapted to receive a plug 26 of midget type, which is connected to a ground lead 27.

lt will thus be seen that I have provided an extremely simple means whereby the radio set may be connected to any suitable outlet. The plug le is merely inserted in any suitable outlet and the antenna and ground leads are plugged into the plug I9.

The plug I5 may be formed integrally by a molding operation or other suitable way, the body being formed of suitable insulating material. This body is provided with a slot through which the end of the cable IG is passed. This end may be anchored to the plug by suitable means, for example a bolt 3| which passes through the plug body and through the cable I0 in the central portion in which the llers I6 are located. If desired, as shown in Fig. 6, the body of the plug i9 may be made in two parts secured together by the bolt 3|.

The generally ilat form of the cable I0 enables me to stow a certain amount of the cable very conveniently in the radio cabinet so that no excess lengths or convolutions of the cable need be exposed. In Figs. l and 2, I have shown a receiving set 28, in which I provide a chamber 29, into which opens a slot 30 through which the cable passes. 1t will readily be understood from Fig. 2 that when the cable is forced inwardly through the slot 30 the cable will arrange itself in zig-zag fashion. As illustrated, the chamber 29 is only slightly wider than the cable and is suitably located in the base of the cabinet, the slot 3D being vertical. It will be understood however that this method of stowing cable is capable of other embodiments, since the flat cable lends itself to easy stowage without risk of tangling.

It is to be noted that with this method of stowing the spacing between the antenna and the other conductors is preserved. Adjacent the inner end the cable I0 is secured to one of the side walls of the chamber 29, which may readily be done since screws, tacks or the like may be passed through the iillers I6 without danger to the conductors or their insulation. The inner end of the cable IIJ passes upwardly from the chamber 29 and its various conductors are connected to the receiving set.

In the modification shown in Figs. '7, 8, and 9 the cable Ill is provided with a plug I9 which is connected to the power outlet 2 I, ground lead 21, and antenna lead 24, in the manner described above. The other or free end is provided with a plug element 32 which comprises sockets 33 which are connected to the conductors I2, I3, I4 and I5. The radio receiving set 28 has mounted thereon a corresponding plug element 34 adapted to receive the plug element 32. With a portable radio receiving set 28 which is to be used in several locations, a plurality of cables ID may be employed which are readily connected and disconnected at the set. Used in this way the ground lead 21 and antenna lead 24 are left permanently connected to the plug I9 and the cable I0, owing to its generally flat form, may be concealed by a rug or the like until it is desired to use the instrument in that location again. Such cables, provided in the locations in which it is desired to operate the instrument enables a modern receiving set to be employed as a portable instrument with much greater convenience than has heretofore been possible. This modication of the invention is particularly adapted for situations where, as is usually the case, the wall outlets are obscured by pieces of furniture and the like. This modication enables the cables to be more or less permanently installed and concealed by floor coverings and the like. In such installation the cable may be held in secured position by tacks or the like which extend through the central portion of the cable and, passing through the fillers I6, do not injure the conductors or their insulation. When the cable thus secured is uncovered, the tacks employed are preferably provided with ornamental heads.

Although the invention has been described in connection with the specific details of preferred embodiments thereof, it must be understood that such details are not intended to be limitative of the invention except insofar as set forth in the accompanying claims.

What I claim as new and desire to secure by Letters Patent is:

l. A radio cable of generally flat form comprising a group of conductors including current conductors and a ground conductor in adjacent relation, a separate antenna conductor, and a, spacer maintaining the antenna conductor in spaced relation to the said group of conductors, all of said conductors and said spacer being arranged in a plane.

2. A radio cable of generally flat form comprising current conductors, a ground conductor, an antenna conductor, and a spacer maintaining the antenna conductor in spaced relation to the other conductors, 'said conductors and spacer being arranged in a plane, and the ground conductor being located between the current conductors and the spacer.

3. A radio conductor of generally flat form comprising insulated current conductors, an insulated ground conductor, an insulated antenna conductor, and a plurality of spacers of low specic inductive capacity and having substantially the same dimensions as the conductors, said conductors and spacers being arranged along side each other with the spacers between the antenna and other conductors.

4. A radio cable comprising current conductors located adjacent each other provided with conductive shields a-dapted to be grounded, an antenna conductor, and means spacing said antenna conductor from the current conductors a greater distance than that between adjacent current conductors.

5. A radio cable of generally flat form comprising current conductors, metallic shields thereon adapted to be grounded, an antenna conductor, and a spacer maintaining the antenna conductor in spaced relation to the current con-- ductors, said conductors and spacer being a1- ranged in a plane.

6. A radio cable of generally ilat form comprising insulated current conductors, metallic shields thereon adapted to be grounded, an nsulated antenna, a plurality of spacers of low specic inductive capacity of substantially the same dimensions as the conductors, said conductors and spacers being arranged along side each other with the spacers between the antenna and other conductors.

7. A radio cable comprising current conductors, a groun-d conductor, an antenna conductor, spacers of low specific inductive capacity, enclosed within a fabric envelope, and threads eX- tending from one side of the envelope to the other and between adjacent conductors and spacers so as to maintain the cable in generally flat form, the antenna conductor being separated from the other conductors by the spacers.

8. In combination, a radio cable of generally flat form comprising current conductors, an antenna conductor and a ground conductor, an-d a plug into which said cable is adapted to enter, said plug being provided with prongs adapted to enter a standard lighting outlet to which prongs the current leads are connected, and being provided with connection elements in its exposed portion to which the antenna and ground conductors are connected.

9. A radio cable plug comprising prongs for cooperating with a standard lighting outlet, means for connecting said prongs to the current conductors of a radio cable, sockets in the eX- posed portion of the plug for receiving antenna and ground plugs, said sockets being adapted to be connected to the antenna and ground conductors of a radio cable.

10. In combination, a radio receiving set' cabinet comprising a chamber of horizontal plan, one of the side walls being provided with a vertical slot, a radio cable of generally flat form secured within the cabinet at a point remote from the slot and extending through the slot, said chamber being substantially rectangular in shape so that when the cable s forced into the: chamber it arranges itself in zigzag formation.

11. A radio cable of generally at form comprising an outer envelope, current conductors, a ground conductor and an antenna conductor located therewithin and arranged in a plane, the current conductors and ground conductor being arranged as adjacent members of a group and the antenna conductor being located in substantially spaced and parallel relation thereto.

' 12. A radio cable of generally flat ribbon-like form comprising current conductors and an antenna conductor, and means spacing said antenna conductor from the current conductors a greater distance than that between adjacent current conductors.

13. A flat radio cable comprising a conductor and a shielded conductor in closely spaced relation and a third conductor on the side of said shielded conductor remote from the first said conductor and spaced from the shielded conductor a greater distance than the distance between said shielded conductor and the rst said conductor.

14. In combination, a radio receiver unit, a flat cable connected to said unit and a plug secured to the end of said cable, said cable including a pair of adjacent alternating current conductors and an antenna conductor spaced from the alternating current conductors greater than the spacing between said alternating current conductors, and said plug carrying elements for connecting antenna and power leads to said conductors.

15. A radio cable of generally flat form cornprising an outer envelope, current conductors and an antenna conductor located therewithin and arranged in a plane, the current conductors being arranged as adjacent members of a group and the antenna conductor being located in substantially spaced and parallel relation thereto.

16. In combination, a radio receiving unit, a at cable connected to said unit and a plug secured to the end of said cable, said cable including a pair of adjacent alternating current conductors and an antenna conductor spaced from the alternating current conductors greater than the spacing between said alternating current conductors, a pair of contacts on said plug adapted to enter a standard outlet to connect said alternating current conductors to power supply, and a connecting element on a portion of said plug exposed when the plug is applied to said outlet for connecting an antenna to said antenna conductor.

EDWARD F. ANDREWS. 

